Abstract
We previously described a dominant suppressor of the splicing defect conferred by an A→;C intron branchpoint mutation in S. cerevisiae. Suppression occurs by increasing the frequency with which the mutant branchpoint is utilized. We have now cloned the genomic region encoding the prp16-1 suppressor function and have demonstrated that PRP16 is essential for viability. A 1071 amino acid open reading frame contains sequence motifs characteristic of an NTP binding fold and further similarities to a superfamily of proteins that includes members with demonstrated RNA-dependent ATPase activity. A single nucleotide change necessary to confer the prp16-1 suppressor phenotype results in a Tyr→Asp substitution near the "A site" consensus for NTP binding proteins. We propose that PRP16 is an excellent candidate for mediating one of the many ATP-requiring steps of spliceosome assembly and that accuracy of branchpoint recognition may be coupled to ATP binding and/or hydrolysis.
Original language | English (US) |
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Pages (from-to) | 705-717 |
Number of pages | 13 |
Journal | Cell |
Volume | 60 |
Issue number | 5 |
DOIs | |
State | Published - Mar 9 1990 |
ASJC Scopus subject areas
- Cell Biology
- Molecular Biology